Blood pressure and heart rate

Conditions: For drinking water, mice were given either tap
water or 1% NaCl (in tap water) 2 wks prior to and during the testing period.

Equipment: BP-2000 Blood Pressure Analysis System (Visitech
Systems, Apex, NC, USA). This machine has four restraining
units (dark metal tunnels open at one end) and a 37°C
warming plate. Computer-automated tail cuffs inflate and
deflate rapidly. Pressure is detected by a photo-resister
cell below each tail and is recorded (computer-assisted data
collection).

Reagents: NaCl from American Bioanalytical (#AB13214)

Animal preparation: Mice were habituated for 7 days on the
equipment prior to testing.

Running: Tail cuffs were placed on the tails of each of
four mice. Blood pressure and heart rate were determined and recorded.
Mice were tested over three days and 20 measurements per day
were collected (see below).

Data collection and analysis: For each mouse, if the
standard deviation over the course of a day exceeded 15 mm
Hg, the data was discarded.

Investigator notes: This non-invasive method was verified by comparing
to an intra-arterial blood pressure method involving anesthetization and
catheterization.